Occupational and Environmental Factors Contributing to Knee Pain in Hospital Staff: Results from a Cross-Sectional Study in Iran

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Given the high prevalence of musculoskeletal disorders among healthcare workers, understanding contributing factors is essential for prevention and health promotion. Materials and Methods A cross-sectional study was conducted among 450 hospital employees. Data were collected through structured questionnaires covering demographic details, employment characteristics (job type, secondary employment, work duration, and shifts), and medical history (personal and family histories, musculoskeletal disorders, knee pain, and smoking). Logistic regression analysis was applied to determine the association between risk factors and reported knee pain. Results Among the participants, 229 (51.1%) reported knee pain. Significant risk factors included older age, female gender, heavy load handling, standing for more than four hours per day, prior use of medication for knee pain, and a history of rheumatic or musculoskeletal disorders. Additionally, lower job satisfaction scores were associated with a higher likelihood of knee pain (P < 0.05). Conclusion Both occupational and non-occupational factors significantly contribute to knee pain among hospital staff. These findings underscore the need for ergonomic interventions and occupational health programs to prevent knee-related issues in healthcare settings. Health sciences/Diseases Health sciences/Health care Health sciences/Health occupations Health sciences/Medical research Health sciences/Risk factors Knee Joints Musculoskeletal Diseases Occupational Health Risk factors Health Personnel Pain Management Introduction Musculoskeletal disorders (MSDs) are recognized as significant and impactful outcomes closely related to occupational factors and challenges across various professions. These disorders substantially affect individual performance and organizational productivity. Among these, knee pain is one of the leading causes of functional disability and reduced quality of life. The knee, as a major joint involved in osteoarthritis (OA), requires special attention, particularly among hospital staff. According to the World Health Organization (WHO), in 2019, out of 538 million individuals diagnosed with OA, 365 million had knee osteoarthritis (Kang et al., 2024 , Guan et al., 2023 ). While OA is one cause of knee pain, other pathological conditions such as patellofemoral issues, bursitis, ligament tears, and meniscal degeneration can also contribute to this problem. Knee pain, a key symptom that affects work performance, has been the subject of interest for many researchers. Previous studies have identified factors such as age, obesity, female gender, and intense physical activity at work as predispositions to knee pain (Gignac et al., 2020 ). However, few studies have examined the impact of occupational hazards on knee pain, with only select professions, such as agriculture and the garment industry, being identified as contributors to knee osteoarthritis and pain. While several investigations have explored MSDs among hospital staff, the impact of occupational risk factors specifically on knee pain in this group has been less discussed. Given the high prevalence of MSDs among hospital staff, reported in previous studies to exceed 43%, and recognizing that knee pain is one of the common complaints within these disorders, this study was designed to identify and evaluate both occupational and non-occupational risk factors contributing to knee pain in hospital employees. Based on a cross-sectional design involving 450 hospital staff members, this research collected demographic, occupational, and clinical data and analysed the associations between various factors through advanced statistical methods such as logistic regression. The ultimate aim of this study is to provide practical insights for developing preventive strategies and improving the occupational health of hospital staff. Materials and Methods This cross-sectional study aimed to investigate the risk factors associated with knee pain among hospital staff at Baharloo Teaching Hospital, located in Tehran, Iran. The study was conducted from October 2023 to August 2024. A total of 450 hospital employees who consented to participate were selected as the study sample. This population was chosen to provide a comprehensive overview of knee pain and its associated factors within this specific occupational group. Participants The participants included staff members working in various departments such as nursing, medicine, physiotherapy, healthcare services, and administrative roles. Inclusion criterion for participation were as follows: Employing hospital work for at least two years Exclusion criteria for participation were as follows: History of meniscal or ligament injuries that could cause knee pain. Previous knee surgery in their medical history. Data Collection The collected data included the following a) Demographic characteristics: age, gender, height, weight, and education level. b) Occupational history: job type, history of second jobs, duration of employment, and work shift type (day or night shifts). c) Medical history: personal and family history of knee issues and pain, presence of any musculoskeletal disorders, and smoking history. d) Daily habits: amount of daily walking, physical activity, and load-bearing habits during the day. e) Standing and sitting time: duration of standing during working hours and time spent sitting. A data collection checklist containing both closed and open-ended questions was used to gather information. The questionnaires were completed in person by the researchers, and all collected data were stored confidentially. Clinical Examination To assess knee misalignment, a clinical method was used. Instead of radiological techniques, the intercondylar distance (ICD) was measured using a precise calliper. The ICD measurement was taken while the participant was standing with relaxed legs. Cases with a distance greater than 6 cm were classified as genu varum. This criterion was based on previous documentation defining normal distances as less than 6 cm. Data Analysis For data analysis, the following steps were taken Descriptive Analysis Results for continuous variables were reported as mean ± standard deviation (Mean ± SD), while categorical variables were presented as frequency and percentages. Univariate Analysis Differences between participants with and without knee pain were assessed using the chi-square test (ꭓ²) for categorical variables and independent t-tests for continuous variables. Multivariate Analysis To identify risk factors for knee pain, logistic regression analysis was performed. The dependent variable was presence or absence of knee pain and independent risk factors such as ICD, age, gender, education level, weight, height, smoking history, job type, work shift, job satisfaction, load-bearing history, physical activity, family history, and positive medical history included in the model. Statistical Criteria Odds ratios (ORs), 95% confidence intervals (CIs), and p-values were reported from the statistical analyses. A p-value less than 0.05 was considered as statistically significant. All statistical analyses were conducted using SPSS version 23 (IBM Corp, Armonk, NY, USA). Ethical Considerations This study was conducted under the supervision of the Ethics Committee of Baharloo Hospital, affiliated with Tehran University of Medical Sciences, with the ethics approval code IR.TUMS.MEDICINE.REC.1402.079. All participants provided written informed consent before the study commenced. All collected data were kept confidential and used solely for research purposes. All methods were performed in accordance with the relevant guidelines and regulations of the institutional and national research ethics committees, and in compliance with the Declaration of Helsinki. Results This study assessed a total of 450 hospital employees, of whom 229 (51.1%) reported experiencing knee pain. The analysis, based on both qualitative and quantitative variables, revealed several significant associations between knee pain and different demographic, occupational, and behavioural factors. These results were thoroughly presented in Tables 1 , 2 , and 3 , providing a comprehensive understanding of the risk factors associated with knee pain among the hospital staff. As shown in Table 1 , gender was one of the qualitative variables significantly related to knee pain. Among the participants, 61.7% were female and 38.3% were male, with a significantly higher prevalence of knee pain in women (67.7%) compared to men (33.3%) (P = 0.008). Occupational role also played a significant part, as 70.9% of participants were healthcare workers and 29.1% were administrative staff. Knee pain was more common among healthcare workers, indicating that their physically demanding job roles may increase the risk of musculoskeletal issues (P = 0.043). Other critical factors associated with knee pain included prolonged standing time, where 68.2% of participants who stood for more than four hours daily reported higher instances of knee pain (P = 0.004), and the lifting of heavy loads, with 41.1% of participants engaged in lifting activities at work experiencing higher knee pain (P = 0.0002). Shift work and family history of knee problems were also positively associated with knee pain, with P-values of 0.001 and 0.001, respectively. Interestingly, only 9.2% of the participants used medication for knee pain, but this group was more likely to report severe knee pain (P = 0.001). On the other hand, variables such as depression history (P = 0.12) and time spent walking at work (P = 0.61) were not associated with knee pain. Quantitative variables were also analysed to determine their association with knee pain, as demonstrated in Table 2 . Age was identified as a significant factor, with participants experiencing knee pain having an average age of 36.62 years, compared to 34.44 years for those without knee pain (P = 0.005). This finding suggests that increasing age increases the likelihood of knee pain, possibly due to cumulative joint wear and tear. Height also appeared to be a contributing factor, with participants suffering from knee pain having a slightly lower average height (167.73 cm) compared to those without knee pain (170.009 cm) (P = 0.007), indicating a biomechanical influence on knee joint stress. Another intriguing finding was the inverse relationship between smoking and knee pain, where participants with knee pain reported fewer years of smoking (0.20 years) compared to those without knee pain (0.88 years) (P = 0.007). Moreover, participants with knee pain reported standing for significantly longer hours per day (8.60 hours) compared to those without knee pain, highlighting the impact of prolonged standing on joint health (P = 0.002). The number of loads lifted also showed a substantial difference, with participants with knee pain lifting an average of 4.88 loads daily, compared to 2.10 loads for those without pain (P = 0.002). The identification of risk factors for knee pain was further refined through multivariate logistic regression analysis, as detailed in Table 3 . Age was confirmed as a significant risk factor, with a positive association between each additional year of age and the likelihood of developing knee pain (B = 0.030, P = 0.037). Female gender also emerged as a key risk factor, with women being at significantly higher risk than men (B=-0.43, P = 0.032). Another noteworthy finding was the link between low job satisfaction and knee pain, as participants with job satisfaction scores below 5 were more prone to knee pain (B=-0.673, P = 0.004). This indicates that psychological factors, such as dissatisfaction with one’s job, may contribute to or exacerbate physical conditions like knee pain. Physical factors remained central to the analysis, with lifting heavy loads being strongly associated with knee pain (B = 0.770, P = 0.001). This finding reinforces the earlier observation that healthcare workers, who often engage in lifting patients or equipment, are at increased risk for musculoskeletal injuries. Additionally, participants who used medication for knee pain were found to be at significantly higher risk (B = 2.413, P = 0.001), suggesting that those who require pharmacological treatment may experience more severe or chronic knee pain. Finally, the presence of rheumatologic and musculoskeletal disorders was significantly linked to knee pain, with individuals suffering from these conditions being more likely to report knee pain (B = 0.886, P = 0.007). Table 1 Association between Qualitative Variables and Knee Pain Based on Chi-Square Test Variable Total Without knee pain Knee pain P-Value Sex Female 272(61.7%) 119(55.3%) 153(67.7%) 0.008 male 169(38.3%) 96(44.7%) 73(33.3%) Job group Office worker 129(29.1%) 73(33.5%) 56(24.8%) 0.043 Health care 315(70.9%) 145(66.5%) 170(75.2%) Depression No 403(91.4%) 201(93.5%) 202(89.4%) 0.12 Yes 38(8.6%) 14(6.5%) 24(10.6%) Standing time ≥ 4 hours 289(68.2%) 126(61.5%) 163(74.4%) 0.004 < 4hours 135(31.8%) 79(38.5%) 56(25.6%) Carrying No 262(58.9%) 147(67.7%) 115(50.4%) 0.0002 Yes 183(41.1%) 70(32.3%) 113(49.6%) Shift work No 189(42.5%) 110(50.7%) 79(34.6%) 0.001 Yes 256(57.5%) 107(49.3%) 149(65.4%) Hold a second job No 390(87.1%) 189(86.3%) 201(87.8%) 0.64 Yes 58(12.9%) 30(13.7%) 28(12.2%) Walking during worktime No 98(22%) 46(21%) 52(23%) 0.61 Yes 347(78%) 173(79%) 174(77%) Smoking No 412(92%) 195(89%) 217(94.8%) 0.026 Yes 36(8%) 24(11%) 12(5.2%) Years of study < 12years 299(73.5%) 153(76.9%) 146(70.2%) 0.12 ≥ 12years 108(26.5%) 46(23.1%) 62(29.8%) Genetic history of genu varum No 356(80.5%) 190(87.2%) 166(74.1%) 0.001 Yes 86(19.5%) 28(12.8%) 58(25.9%) Using drug for knee pain No 403(90.8%) 216(99.1%) 187(82.7%) 0.001 Yes 41(9.2%) 2(0.9%) 39(17.3%) Job satisfaction < 5 154(35.4%) 57(26.8%) 97(43.7%) 0.000 ≥ 5 281(64.6%) 156(73.2%) 125(56.3%) Rheumatologic or musculoskeletal disease No 362(83.4%) 196(91.6%) 166(75.5%) 0.000 Yes 72(16.6%) 18(8.4%) 54(24.5%) ICD < 6 306(68.3%) 149(68%) 157(68.6%) 0.9 ≥ 6 142(31.7%) 70(32%) 72(31.4%) Table 2 Correlation between Quantitative Variables and Knee Pain Based on Independent T-Test Analysis variables Mean (SD) Without knee pain Mean (SD) With knee pain Mean (SD) Mean difference P value Age (year) 35.56 (8.17) 34.44(8.6) 36.62(7.56) 2.17 0.005 Weight (kg) 72.21 (13.63) 72.87(14.16) 71.54(13.12) -1.32 0.30 Height (cm) 168.93 (9.30) 170.009(9.07) 167.73(9.35) -2.35 0.007 Cigarette per day 0.75 (3.09) 0.94(3.38) 0.55(2.79) -0.38 0.18 Years of smoking 0.56 (2.74) 0.88(3.58) 0.20(1.20) -0.676 0.007 Current work experience (years) 9.28 (7.07) 8.41(7.39) 10.11(6.70) 1.70 0.01 Previous work experience (years) 3.11 (5.37) 2.79(4.78) 3.39(5.78) 0.594 0.27 Standing at work (hours) 7.75 (5.93) 6.5(5.70) 8.60(6.05) 1.75 0.002 Carrying number in every shift 3.51 (9.23) 2.10(6.57) 4.88(11.07) 2.77 0.002 Walking time (hours) 2.38 (3.87) 2.06(3.63) 2.70(4.08) 0.64 0.08 Intercondylar distance (cm) 4.11(2.94) 4.08(2.93) 4.12(2.95) 0.04 0.87 Sum weight carrying in every shift 40.38(165.96) 19.72(88.93) 59.97(213.22) 40.25 0.01 Table 3 Risk Factors for Knee Pain among Hospital Staff Identified Through Logistic Regression Analysis Knee pain factors B P-value EXP (B) 95% C.I. for EXP (B) Lower Upper Age 0.030 0.037 1.030 1.002 1.059 Sex -0.493 0.032 0.611 0.389 0.958 Job Satisfaction − .0.673 0.004 0.510 0.323 0.806 Carrying 0.770 0.001 2.159 1.380 3.378 Drug for knee pain 2.413 0.001 11.171 2.551 48.918 Disease 0.886 0.007 2.426 1.267 4.645 Constant -0.973 0.058 0.378 R square = 0.213 Discussion In the present study, the prevalence of knee pain among hospital employees was found to be 51.1%, which is significantly higher than the general statistics indicating that the prevalence of knee pain in the adult population is approximately 25–28%. Previous studies have shown that knee pain is a common cause of functional limitation and reduced quality of life. Notably, a study conducted in Framingham reported a two-fold increase in men and a three-fold increase in women in the prevalence of knee pain over a 20-year period (Wallace et al., 2017 ). The results of this study underscore the importance of recognizing knee pain among hospital employees as a serious issue and highlight the need for assessing its risk factors. Risk Factors: The present study identified several risk factors for knee pain, including age, gender, occupation type, work experience, and job dissatisfaction. These findings are consistent with previous research, which similarly identified factors like age and gender as key risk factors for knee pain (Wang et al., 2020 ). Interestingly, despite the expectation of a correlation between weight and knee pain, no significant association was found between these two variables. This could be due to the relatively small sample size of hospital staff specifically examined in this study. Previous research, including a study by (Dubé et al., 2016 ), suggested an association between smoking and knee pain, indicating that smoking may be linked to reduced pain. Our results showed that non-smokers experienced more knee pain than smokers. This finding aligns with systematic reviews and meta-analyses reporting the anti-inflammatory effects of nicotine in pain relief (Luo et al., 2023 ). Occupational Factors: Occupational factors also played a significant role in the prevalence of knee pain among hospital staff. Healthcare workers, such as doctors and nurses, reported higher rates of knee pain compared to administrative staff. These results are in line with the findings of (Krishnan et al., 2021 , Dantas et al., 2023) who reported that healthcare workers are at higher risk for musculoskeletal disorders due to physical and psychological demands. Additionally, shift work and irregular working hours were identified as risk factors for knee pain. Evidence suggests that long and irregular work hours place additional stress on the knees, leading to pain. Our study also found that standing for more than four hours was identified as a risk factor for knee pain, this result is consistent with findings from other studies that indicate prolonged standing leads to knee pain (Coenen et al., 2017 , Tahir et al., 2023 ). Furthermore, our results demonstrated a significant association between job dissatisfaction and increased knee pain. These results are consistent with other studies showing that job-related stress and high physical demands can lead to musculoskeletal pain (de Andrade Ruela et al., 2022 , Kwon et al., 2023 ). This emphasizes the need to improve working conditions and increase job satisfaction among hospital employees to reduce the incidence of knee pain. Implications and Future Research: Given the high prevalence of knee pain among hospital employees and the identified risk factors, it is essential for policymakers and healthcare managers to focus on preventive and corrective interventions. Future studies should aim to explore the causal relationships between these risk factors and knee pain in hospital employees. The findings of this study provide valuable insights into the significant correlations between various factors and the occurrence of knee pain, which can serve as a foundation for designing preventive programs and improving working conditions for hospital staff. Identified factors, such as age, gender, job satisfaction, and medical history, should be considered in healthcare policies to help reduce the incidence of knee pain. Limitations: This study was conducted as a cross-sectional study, limiting the ability to establish causality. Additionally, the relatively small sample size and reliance on self-reported data may have affected the accuracy of the results. Furthermore, variables such as diet and physical activity should be considered in future research. Despite these limitations, the study provides important insights into the prevalence and risk factors of knee pain in hospital employees. Conclusion This study revealed that the prevalence of knee pain among hospital employees is 51.1%, indicating a significant public health concern within this occupational group. The identified risk factors include age, gender, type of occupation (healthcare workers compared to administrative staff), lifting loads, smoking status, shift work, family history of knee problems, standing for more than four hours per day, job dissatisfaction, and a history of rheumatologic or musculoskeletal disorders. These findings emphasize the necessity for preventive interventions and health programs to reduce the prevalence of knee pain and enhance the quality of life for hospital employees, particularly in the context of the identified risk factors. Declarations Availability of data and material: The data supporting the findings of this study are available from the corresponding author upon reasonable request. Competing interests : The authors declare that they have no competing interests. Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Author contributions: All authors have made significant contributions to the study and the preparation of the manuscript. Acknowledgements: The authors wish to express their sincere gratitude to the staff and management of Baharloo Hospital, Tehran University of Medical Sciences (TUMS), for their invaluable support. References COENEN, P., PARRY, S., WILLENBERG, L., SHI, J. 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Proceedings of the National Academy of Sciences, 114 , 9332-9336. WANG, X., PERRY, T. A., ARDEN, N., CHEN, L., PARSONS, C. M., COOPER, C., GATES, L. & HUNTER, D. J. 2020. Occupational risk in knee osteoarthritis: a systematic review and meta‐analysis of observational studies. Arthritis care & research, 72 , 1213-1223. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7942810","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":545742981,"identity":"a5181573-e512-4889-bbb8-cc202c48567f","order_by":0,"name":"Navidreza Zamani","email":"","orcid":"","institution":"Tehran University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Navidreza","middleName":"","lastName":"Zamani","suffix":""},{"id":545742982,"identity":"45bfb92f-2e53-46f2-b53e-c7f605832643","order_by":1,"name":"Hamidreza Pouragha","email":"","orcid":"","institution":"Mehr Alborz 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07:11:16","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":279086,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7942810/v1/b510268c-9fa1-476b-8aea-0ad925ec59ec.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eOccupational and Environmental Factors Contributing to Knee Pain in Hospital Staff: Results from a Cross-Sectional Study in Iran\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMusculoskeletal disorders (MSDs) are recognized as significant and impactful outcomes closely related to occupational factors and challenges across various professions. These disorders substantially affect individual performance and organizational productivity. Among these, knee pain is one of the leading causes of functional disability and reduced quality of life. The knee, as a major joint involved in osteoarthritis (OA), requires special attention, particularly among hospital staff. According to the World Health Organization (WHO), in 2019, out of 538\u0026nbsp;million individuals diagnosed with OA, 365\u0026nbsp;million had knee osteoarthritis (Kang et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2024\u003c/span\u003e, Guan et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). While OA is one cause of knee pain, other pathological conditions such as patellofemoral issues, bursitis, ligament tears, and meniscal degeneration can also contribute to this problem.\u003c/p\u003e\u003cp\u003eKnee pain, a key symptom that affects work performance, has been the subject of interest for many researchers. Previous studies have identified factors such as age, obesity, female gender, and intense physical activity at work as predispositions to knee pain (Gignac et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). However, few studies have examined the impact of occupational hazards on knee pain, with only select professions, such as agriculture and the garment industry, being identified as contributors to knee osteoarthritis and pain. While several investigations have explored MSDs among hospital staff, the impact of occupational risk factors specifically on knee pain in this group has been less discussed.\u003c/p\u003e\u003cp\u003eGiven the high prevalence of MSDs among hospital staff, reported in previous studies to exceed 43%, and recognizing that knee pain is one of the common complaints within these disorders, this study was designed to identify and evaluate both occupational and non-occupational risk factors contributing to knee pain in hospital employees. Based on a cross-sectional design involving 450 hospital staff members, this research collected demographic, occupational, and clinical data and analysed the associations between various factors through advanced statistical methods such as logistic regression. The ultimate aim of this study is to provide practical insights for developing preventive strategies and improving the occupational health of hospital staff.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eThis cross-sectional study aimed to investigate the risk factors associated with knee pain among hospital staff at Baharloo Teaching Hospital, located in Tehran, Iran. The study was conducted from October 2023 to August 2024. A total of 450 hospital employees who consented to participate were selected as the study sample. This population was chosen to provide a comprehensive overview of knee pain and its associated factors within this specific occupational group.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eParticipants\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe participants included staff members working in various departments such as nursing, medicine, physiotherapy, healthcare services, and administrative roles.\u003c/p\u003e\n\u003cp\u003eInclusion criterion for participation were as follows:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eEmploying hospital work for at least two years\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eExclusion criteria for participation were as follows:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eHistory of meniscal or ligament injuries that could cause knee pain.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003ePrevious knee surgery in their medical history.\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eData Collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe collected data included the following\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ea)\u003c/strong\u003e Demographic characteristics: age, gender, height, weight, and education level.\u003cbr\u003e\u003cstrong\u003eb)\u003c/strong\u003e Occupational history: job type, history of second jobs, duration of employment, and work shift type (day or night shifts).\u003cbr\u003e\u003cstrong\u003ec)\u003c/strong\u003e Medical history: personal and family history of knee issues and pain, presence of any musculoskeletal disorders, and smoking history.\u003cbr\u003e\u003cstrong\u003ed)\u003c/strong\u003e Daily habits: amount of daily walking, physical activity, and load-bearing habits during the day.\u003cbr\u003e\u003cstrong\u003ee)\u003c/strong\u003e Standing and sitting time: duration of standing during working hours and time spent sitting.\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003eA data collection checklist containing both closed and open-ended questions was used to gather information. The questionnaires were completed in person by the researchers, and all collected data were stored confidentially.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Examination\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo assess knee misalignment, a clinical method was used. Instead of radiological techniques, the intercondylar distance (ICD) was measured using a precise calliper. The ICD measurement was taken while the participant was standing with relaxed legs. Cases with a distance greater than 6 cm were classified as genu varum. This criterion was based on previous documentation defining normal distances as less than 6 cm.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor data analysis, the following steps were taken\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDescriptive Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eResults for continuous variables were reported as mean ± standard deviation (Mean ± SD), while categorical variables were presented as frequency and percentages.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUnivariate Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDifferences between participants with and without knee pain were assessed using the chi-square test (ꭓ²) for categorical variables and independent t-tests for continuous variables.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMultivariate Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo identify risk factors for knee pain, logistic regression analysis was performed. The dependent variable was presence or absence of knee pain and independent risk factors such as ICD, age, gender, education level, weight, height, smoking history, job type, work shift, job satisfaction, load-bearing history, physical activity, family history, and positive medical history included in the model.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Criteria\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOdds ratios (ORs), 95% confidence intervals (CIs), and p-values were reported from the statistical analyses. A p-value less than 0.05 was considered as statistically significant. All statistical analyses were conducted using SPSS version 23 (IBM Corp, Armonk, NY, USA).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Considerations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted under the supervision of the Ethics Committee of Baharloo Hospital, affiliated with Tehran University of Medical Sciences, with the ethics approval code IR.TUMS.MEDICINE.REC.1402.079. All participants provided written informed consent before the study commenced. All collected data were kept confidential and used solely for research purposes. All methods were performed in accordance with the relevant guidelines and regulations of the institutional and national research ethics committees, and in compliance with the Declaration of Helsinki.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThis study assessed a total of 450 hospital employees, of whom 229 (51.1%) reported experiencing knee pain. The analysis, based on both qualitative and quantitative variables, revealed several significant associations between knee pain and different demographic, occupational, and behavioural factors. These results were thoroughly presented in Tables\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, and \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, providing a comprehensive understanding of the risk factors associated with knee pain among the hospital staff.\u003c/p\u003e\u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, gender was one of the qualitative variables significantly related to knee pain. Among the participants, 61.7% were female and 38.3% were male, with a significantly higher prevalence of knee pain in women (67.7%) compared to men (33.3%) (P\u0026thinsp;=\u0026thinsp;0.008). Occupational role also played a significant part, as 70.9% of participants were healthcare workers and 29.1% were administrative staff. Knee pain was more common among healthcare workers, indicating that their physically demanding job roles may increase the risk of musculoskeletal issues (P\u0026thinsp;=\u0026thinsp;0.043). Other critical factors associated with knee pain included prolonged standing time, where 68.2% of participants who stood for more than four hours daily reported higher instances of knee pain (P\u0026thinsp;=\u0026thinsp;0.004), and the lifting of heavy loads, with 41.1% of participants engaged in lifting activities at work experiencing higher knee pain (P\u0026thinsp;=\u0026thinsp;0.0002). Shift work and family history of knee problems were also positively associated with knee pain, with P-values of 0.001 and 0.001, respectively. Interestingly, only 9.2% of the participants used medication for knee pain, but this group was more likely to report severe knee pain (P\u0026thinsp;=\u0026thinsp;0.001). On the other hand, variables such as depression history (P\u0026thinsp;=\u0026thinsp;0.12) and time spent walking at work (P\u0026thinsp;=\u0026thinsp;0.61) were not associated with knee pain.\u003c/p\u003e\u003cp\u003eQuantitative variables were also analysed to determine their association with knee pain, as demonstrated in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Age was identified as a significant factor, with participants experiencing knee pain having an average age of 36.62 years, compared to 34.44 years for those without knee pain (P\u0026thinsp;=\u0026thinsp;0.005). This finding suggests that increasing age increases the likelihood of knee pain, possibly due to cumulative joint wear and tear. Height also appeared to be a contributing factor, with participants suffering from knee pain having a slightly lower average height (167.73 cm) compared to those without knee pain (170.009 cm) (P\u0026thinsp;=\u0026thinsp;0.007), indicating a biomechanical influence on knee joint stress. Another intriguing finding was the inverse relationship between smoking and knee pain, where participants with knee pain reported fewer years of smoking (0.20 years) compared to those without knee pain (0.88 years) (P\u0026thinsp;=\u0026thinsp;0.007). Moreover, participants with knee pain reported standing for significantly longer hours per day (8.60 hours) compared to those without knee pain, highlighting the impact of prolonged standing on joint health (P\u0026thinsp;=\u0026thinsp;0.002). The number of loads lifted also showed a substantial difference, with participants with knee pain lifting an average of 4.88 loads daily, compared to 2.10 loads for those without pain (P\u0026thinsp;=\u0026thinsp;0.002).\u003c/p\u003e\u003cp\u003eThe identification of risk factors for knee pain was further refined through multivariate logistic regression analysis, as detailed in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Age was confirmed as a significant risk factor, with a positive association between each additional year of age and the likelihood of developing knee pain (B\u0026thinsp;=\u0026thinsp;0.030, P\u0026thinsp;=\u0026thinsp;0.037). Female gender also emerged as a key risk factor, with women being at significantly higher risk than men (B=-0.43, P\u0026thinsp;=\u0026thinsp;0.032). Another noteworthy finding was the link between low job satisfaction and knee pain, as participants with job satisfaction scores below 5 were more prone to knee pain (B=-0.673, P\u0026thinsp;=\u0026thinsp;0.004). This indicates that psychological factors, such as dissatisfaction with one\u0026rsquo;s job, may contribute to or exacerbate physical conditions like knee pain.\u003c/p\u003e\u003cp\u003ePhysical factors remained central to the analysis, with lifting heavy loads being strongly associated with knee pain (B\u0026thinsp;=\u0026thinsp;0.770, P\u0026thinsp;=\u0026thinsp;0.001). This finding reinforces the earlier observation that healthcare workers, who often engage in lifting patients or equipment, are at increased risk for musculoskeletal injuries. Additionally, participants who used medication for knee pain were found to be at significantly higher risk (B\u0026thinsp;=\u0026thinsp;2.413, P\u0026thinsp;=\u0026thinsp;0.001), suggesting that those who require pharmacological treatment may experience more severe or chronic knee pain. Finally, the presence of rheumatologic and musculoskeletal disorders was significantly linked to knee pain, with individuals suffering from these conditions being more likely to report knee pain (B\u0026thinsp;=\u0026thinsp;0.886, P\u0026thinsp;=\u0026thinsp;0.007).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAssociation between Qualitative Variables and Knee Pain Based on Chi-Square Test\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eWithout\u003c/p\u003e\u003cp\u003eknee pain\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eKnee pain\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eP-Value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" 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colname=\"c4\"\u003e\u003cp\u003e96(44.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e73(33.3%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eJob group\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eOffice worker\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e129(29.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e73(33.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e56(24.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.043\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eHealth care\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e315(70.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e145(66.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e170(75.2%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eDepression\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e403(91.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e201(93.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e202(89.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.12\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e38(8.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e14(6.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e24(10.6%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eStanding time\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026ge;\u0026thinsp;4 hours\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e289(68.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e126(61.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e163(74.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;4hours\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e135(31.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e79(38.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e56(25.6%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eCarrying\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e262(58.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e147(67.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e115(50.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.0002\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e183(41.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e70(32.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e113(49.6%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eShift work\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e189(42.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e110(50.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e79(34.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e256(57.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e107(49.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e149(65.4%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eHold a second job\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e390(87.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e189(86.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e201(87.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.64\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e58(12.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e30(13.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e28(12.2%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eWalking during worktime\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e98(22%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e46(21%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e52(23%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.61\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e347(78%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e173(79%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e174(77%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eSmoking\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e412(92%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e195(89%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e217(94.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.026\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e36(8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24(11%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12(5.2%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eYears of study\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;12years\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e299(73.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e153(76.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e146(70.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.12\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026ge;\u0026thinsp;12years\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e108(26.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e46(23.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e62(29.8%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eGenetic history of genu varum\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e356(80.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e190(87.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e166(74.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e86(19.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e28(12.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e58(25.9%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eUsing drug for knee pain\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e403(90.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e216(99.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e187(82.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e41(9.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2(0.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e39(17.3%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eJob satisfaction\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;5\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e154(35.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e57(26.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e97(43.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.000\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026ge;\u0026thinsp;5\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e281(64.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e156(73.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e125(56.3%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eRheumatologic or musculoskeletal disease\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNo\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e362(83.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e196(91.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e166(75.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.000\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e72(16.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e18(8.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e54(24.5%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eICD\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;6\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e306(68.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e149(68%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e157(68.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e\u0026ge;\u0026thinsp;6\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e142(31.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e70(32%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e72(31.4%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eCorrelation between Quantitative Variables and Knee Pain Based on Independent T-Test Analysis\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003evariables\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMean (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eWithout knee pain\u003c/p\u003e\u003cp\u003eMean (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eWith knee pain\u003c/p\u003e\u003cp\u003eMean (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMean difference\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eP value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (year)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e35.56 (8.17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e34.44(8.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e36.62(7.56)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.005\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWeight (kg)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e72.21 (13.63)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e72.87(14.16)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e71.54(13.12)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-1.32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.30\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHeight (cm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e168.93 (9.30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e170.009(9.07)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e167.73(9.35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-2.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.007\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCigarette per day\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.75 (3.09)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.94(3.38)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.55(2.79)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-0.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.18\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYears of smoking\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.56 (2.74)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.88(3.58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.20(1.20)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-0.676\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.007\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCurrent work experience (years)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9.28 (7.07)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.41(7.39)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10.11(6.70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.70\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePrevious work experience (years)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3.11 (5.37)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.79(4.78)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e3.39(5.78)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.594\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.27\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStanding at work (hours)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7.75 (5.93)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6.5(5.70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e8.60(6.05)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.002\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCarrying number in every shift\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3.51 (9.23)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.10(6.57)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e4.88(11.07)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.77\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.002\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWalking time (hours)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2.38 (3.87)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.06(3.63)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.70(4.08)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.08\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIntercondylar distance (cm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e4.11(2.94)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4.08(2.93)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e4.12(2.95)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.87\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSum weight carrying in every shift\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e40.38(165.96)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e19.72(88.93)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e59.97(213.22)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e40.25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eRisk Factors for Knee Pain among Hospital Staff Identified Through Logistic Regression Analysis\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eKnee pain factors\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eEXP (B)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003e95% C.I. for EXP (B)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eLower\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eUpper\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAge\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.030\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.037\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1.030\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.002\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.059\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSex\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e-0.493\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.032\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.611\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.389\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.958\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eJob Satisfaction\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.0.673\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.510\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.323\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.806\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCarrying\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.770\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.159\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.380\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e3.378\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eDrug for knee pain\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2.413\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.171\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.551\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e48.918\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eDisease\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.886\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.007\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.426\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.267\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e4.645\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eConstant\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e-0.973\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.058\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.378\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eR square = 0.213\u003c/h3\u003e\n"},{"header":"Discussion","content":"\u003cp\u003eIn the present study, the prevalence of knee pain among hospital employees was found to be 51.1%, which is significantly higher than the general statistics indicating that the prevalence of knee pain in the adult population is approximately 25\u0026ndash;28%. Previous studies have shown that knee pain is a common cause of functional limitation and reduced quality of life. Notably, a study conducted in Framingham reported a two-fold increase in men and a three-fold increase in women in the prevalence of knee pain over a 20-year period (Wallace et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). The results of this study underscore the importance of recognizing knee pain among hospital employees as a serious issue and highlight the need for assessing its risk factors.\u003c/p\u003e\u003cp\u003eRisk Factors: The present study identified several risk factors for knee pain, including age, gender, occupation type, work experience, and job dissatisfaction. These findings are consistent with previous research, which similarly identified factors like age and gender as key risk factors for knee pain (Wang et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Interestingly, despite the expectation of a correlation between weight and knee pain, no significant association was found between these two variables. This could be due to the relatively small sample size of hospital staff specifically examined in this study.\u003c/p\u003e\u003cp\u003ePrevious research, including a study by (Dub\u0026eacute; et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2016\u003c/span\u003e), suggested an association between smoking and knee pain, indicating that smoking may be linked to reduced pain. Our results showed that non-smokers experienced more knee pain than smokers. This finding aligns with systematic reviews and meta-analyses reporting the anti-inflammatory effects of nicotine in pain relief (Luo et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eOccupational Factors: Occupational factors also played a significant role in the prevalence of knee pain among hospital staff. Healthcare workers, such as doctors and nurses, reported higher rates of knee pain compared to administrative staff. These results are in line with the findings of (Krishnan et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Dantas et al., 2023) who reported that healthcare workers are at higher risk for musculoskeletal disorders due to physical and psychological demands. Additionally, shift work and irregular working hours were identified as risk factors for knee pain. Evidence suggests that long and irregular work hours place additional stress on the knees, leading to pain.\u003c/p\u003e\u003cp\u003eOur study also found that standing for more than four hours was identified as a risk factor for knee pain, this result is consistent with findings from other studies that indicate prolonged standing leads to knee pain (Coenen et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2017\u003c/span\u003e, Tahir et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eFurthermore, our results demonstrated a significant association between job dissatisfaction and increased knee pain. These results are consistent with other studies showing that job-related stress and high physical demands can lead to musculoskeletal pain (de Andrade Ruela et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Kwon et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). This emphasizes the need to improve working conditions and increase job satisfaction among hospital employees to reduce the incidence of knee pain.\u003c/p\u003e\u003cp\u003eImplications and Future Research: Given the high prevalence of knee pain among hospital employees and the identified risk factors, it is essential for policymakers and healthcare managers to focus on preventive and corrective interventions. Future studies should aim to explore the causal relationships between these risk factors and knee pain in hospital employees. The findings of this study provide valuable insights into the significant correlations between various factors and the occurrence of knee pain, which can serve as a foundation for designing preventive programs and improving working conditions for hospital staff. Identified factors, such as age, gender, job satisfaction, and medical history, should be considered in healthcare policies to help reduce the incidence of knee pain.\u003c/p\u003e\u003cp\u003eLimitations: This study was conducted as a cross-sectional study, limiting the ability to establish causality. Additionally, the relatively small sample size and reliance on self-reported data may have affected the accuracy of the results. Furthermore, variables such as diet and physical activity should be considered in future research. Despite these limitations, the study provides important insights into the prevalence and risk factors of knee pain in hospital employees.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study revealed that the prevalence of knee pain among hospital employees is 51.1%, indicating a significant public health concern within this occupational group. The identified risk factors include age, gender, type of occupation (healthcare workers compared to administrative staff), lifting loads, smoking status, shift work, family history of knee problems, standing for more than four hours per day, job dissatisfaction, and a history of rheumatologic or musculoskeletal disorders. These findings emphasize the necessity for preventive interventions and health programs to reduce the prevalence of knee pain and enhance the quality of life for hospital employees, particularly in the context of the identified risk factors.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAvailability of data and material:\u0026nbsp;\u003c/strong\u003eThe data supporting the findings of this study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eCompeting interests\u003c/strong\u003e: The authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions:\u0026nbsp;\u003c/strong\u003eAll authors have made significant contributions to the study and the preparation of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eThe authors wish to express their sincere gratitude to the staff and management of Baharloo Hospital, Tehran University of Medical Sciences (TUMS), for their invaluable support.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCOENEN, P., PARRY, S., WILLENBERG, L., SHI, J. W., ROMERO, L., BLACKWOOD, D. M., HEALY, G. N., DUNSTAN, D. W. \u0026amp; STRAKER, L. M. 2017. Associations of prolonged standing with musculoskeletal symptoms\u0026mdash;A systematic review of laboratory studies. \u003cem\u003eGait \u0026amp; posture,\u003c/em\u003e 58\u003cstrong\u003e,\u003c/strong\u003e 310-318.\u003c/li\u003e\n\u003cli\u003eDANTAS, G. D. S. V., CARDOSO, J. P. \u0026amp; DE ARA\u0026Uacute;JO, T. M. 2023. Association between physical and psychosocial demands and musculoskeletal pain in health workers. \u003cem\u003eRevista Brasileira de Medicina do Trabalho,\u003c/em\u003e 20\u003cstrong\u003e,\u003c/strong\u003e 524.\u003c/li\u003e\n\u003cli\u003eDE ANDRADE RUELA, G., BARRETO, S. M., GRIEP, R. H., BENSE\u0026Ntilde;OR, I. M., TELLES, R. W. \u0026amp; CAMELO, L. V. 2022. Job stress and chronic and widespread musculoskeletal pain: a cross-sectional analysis from the Brazilian Longitudinal Study of Adult Health Musculoskeletal. \u003cem\u003ePain,\u003c/em\u003e 163\u003cstrong\u003e,\u003c/strong\u003e 2044-2051.\u003c/li\u003e\n\u003cli\u003eDUB\u0026Eacute;, C. E., LIU, S.-H., DRIBAN, J. B., MCALINDON, T. E., EATON, C. B. \u0026amp; LAPANE, K. L. 2016. The relationship between smoking and knee osteoarthritis in the Osteoarthritis Initiative. \u003cem\u003eOsteoarthritis and cartilage,\u003c/em\u003e 24\u003cstrong\u003e,\u003c/strong\u003e 465-472.\u003c/li\u003e\n\u003cli\u003eGIGNAC, M. A., IRVIN, E., CULLEN, K., VAN EERD, D., BEATON, D. E., MAHOOD, Q., MCLEOD, C. \u0026amp; BACKMAN, C. L. 2020. Men and women\u0026apos;s occupational activities and the risk of developing osteoarthritis of the knee, hip, or hands: a systematic review and recommendations for future research. \u003cem\u003eArthritis care \u0026amp; research,\u003c/em\u003e 72\u003cstrong\u003e,\u003c/strong\u003e 378-396.\u003c/li\u003e\n\u003cli\u003eGUAN, B., ANDERSON, D. B., CHEN, L., FENG, S. \u0026amp; ZHOU, H. 2023. Global, regional and national burden of traumatic brain injury and spinal cord injury, 1990\u0026ndash;2019: A systematic analysis for the Global Burden of Disease Study 2019. \u003cem\u003eBMJ open,\u003c/em\u003e 13\u003cstrong\u003e,\u003c/strong\u003e e075049.\u003c/li\u003e\n\u003cli\u003eKANG, Y., LIU, C., JI, Y., ZHANG, H., WANG, Y., BI, W., XU, J. \u0026amp; GUO, B. 2024. The burden of knee osteoarthritis worldwide, regionally, and nationally from 1990 to 2019, along with an analysis of cross-national inequalities. \u003cem\u003eArchives of Orthopaedic and Trauma Surgery,\u003c/em\u003e 144\u003cstrong\u003e,\u003c/strong\u003e 2731-2743.\u003c/li\u003e\n\u003cli\u003eKRISHNAN, K. S., RAJU, G. \u0026amp; SHAWKATALY, O. 2021. Prevalence of work-related musculoskeletal disorders: Psychological and physical risk factors. \u003cem\u003eInternational journal of environmental research and public health,\u003c/em\u003e 18\u003cstrong\u003e,\u003c/strong\u003e 9361.\u003c/li\u003e\n\u003cli\u003eKWON, S., LEE, S.-J., BAO, S., DE CASTRO, A., HERTING, J. R. \u0026amp; JOHNSON, K. 2023. Interaction between physical demands and job strain on musculoskeletal symptoms and work performance. \u003cem\u003eErgonomics,\u003c/em\u003e 66\u003cstrong\u003e,\u003c/strong\u003e 34-48.\u003c/li\u003e\n\u003cli\u003eLUO, Y., YANG, Y., SCHNEIDER, C. \u0026amp; BALLE, T. 2023. The Anti-nociceptive effects of Nicotine in humans: a systematic review and Meta-analysis. \u003cem\u003ePharmaceuticals,\u003c/em\u003e 16\u003cstrong\u003e,\u003c/strong\u003e 1665.\u003c/li\u003e\n\u003cli\u003eTAHIR, M., MAQSOOD, M., AZHAR, N., SAFDAR, Z., AMIN, U. \u0026amp; WAHEED, T. S. 2023. Association of knee pain in long standing and sitting among university teachers: association of knee pain in university teachers. \u003cem\u003eThe Healer Journal of Physiotherapy and Rehabilitation Sciences,\u003c/em\u003e 3\u003cstrong\u003e,\u003c/strong\u003e 314-321.\u003c/li\u003e\n\u003cli\u003eWALLACE, I. J., WORTHINGTON, S., FELSON, D. T., JURMAIN, R. D., WREN, K. T., MAIJANEN, H., WOODS, R. J. \u0026amp; LIEBERMAN, D. E. 2017. Knee osteoarthritis has doubled in prevalence since the mid-20th century. \u003cem\u003eProceedings of the National Academy of Sciences,\u003c/em\u003e 114\u003cstrong\u003e,\u003c/strong\u003e 9332-9336.\u003c/li\u003e\n\u003cli\u003eWANG, X., PERRY, T. A., ARDEN, N., CHEN, L., PARSONS, C. M., COOPER, C., GATES, L. \u0026amp; HUNTER, D. J. 2020. Occupational risk in knee osteoarthritis: a systematic review and meta‐analysis of observational studies. \u003cem\u003eArthritis care \u0026amp; research,\u003c/em\u003e 72\u003cstrong\u003e,\u003c/strong\u003e 1213-1223.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Knee Joints, Musculoskeletal Diseases, Occupational Health, Risk factors, Health Personnel, Pain Management","lastPublishedDoi":"10.21203/rs.3.rs-7942810/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7942810/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e\u003cp\u003eThis study aimed to identify occupational and non-occupational risk factors associated with knee pain among staff at Baharloo Teaching Hospital in Tehran, Iran. Given the high prevalence of musculoskeletal disorders among healthcare workers, understanding contributing factors is essential for prevention and health promotion.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e\u003cp\u003eA cross-sectional study was conducted among 450 hospital employees. Data were collected through structured questionnaires covering demographic details, employment characteristics (job type, secondary employment, work duration, and shifts), and medical history (personal and family histories, musculoskeletal disorders, knee pain, and smoking). Logistic regression analysis was applied to determine the association between risk factors and reported knee pain.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eAmong the participants, 229 (51.1%) reported knee pain. Significant risk factors included older age, female gender, heavy load handling, standing for more than four hours per day, prior use of medication for knee pain, and a history of rheumatic or musculoskeletal disorders. Additionally, lower job satisfaction scores were associated with a higher likelihood of knee pain (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eBoth occupational and non-occupational factors significantly contribute to knee pain among hospital staff. These findings underscore the need for ergonomic interventions and occupational health programs to prevent knee-related issues in healthcare settings.\u003c/p\u003e","manuscriptTitle":"Occupational and Environmental Factors Contributing to Knee Pain in Hospital Staff: Results from a Cross-Sectional Study in Iran","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-17 08:31:36","doi":"10.21203/rs.3.rs-7942810/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"38d2d87b-cc5c-42e3-a793-bcbd23c717a6","owner":[],"postedDate":"November 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":58092598,"name":"Health sciences/Diseases"},{"id":58092599,"name":"Health sciences/Health care"},{"id":58092600,"name":"Health sciences/Health occupations"},{"id":58092601,"name":"Health sciences/Medical research"},{"id":58092602,"name":"Health sciences/Risk factors"}],"tags":[],"updatedAt":"2026-05-22T07:10:42+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-17 08:31:36","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7942810","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7942810","identity":"rs-7942810","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}